Electric seam-welding machine



May 2o 1924.

G. H. sc'zHKoMMoDAU ELECTRIC SEAM WELDING MACHINE Filed Nov. 29 1918 3 She'ets-Shet l May zo, 19:24J 1,494,713

G. H. SCHKOMMODAU ELECTRIC SEAM WELDING MACHNE Filed Nov. 29 1918 3 Sheets-Sheet 2 May 20 1924. Y 1,494,713

G. H. SCHKOMMODAU rLrsc'rRIc:` sEAM WELDING MACHINE l Filed Nov. 2; .l 1918 s sheets-sheer Fg g 3 o l 3 76 7 f? 7 f8 2.4 6I 6766 23 f Patent-ea. May 20, 19.24,

UNIfrED STATES 1,494,113 PATEN'Il orrics. f

ausm-vsn scrixomconau, or LYNN, MAssAcnUsnrrs, ssxonon To mensole -ELEcrnrc WELDING courANY, or LYNN, msncnusms, A CORPORATION o r MASSACHUSETTS.

ELECTBlIC SEAMWUELDING um .application mea revenue: as, :auf semi n. geen.

To nllm/o-m. it may concern:

Be it known that I, Gos'rave H. Sermon:- MODAU, a citizen' of the United States, and a resident ct Lynn,'i n the county of Essex and State of Massachusetts, have invented cerftai'n new a dnseful Inu'irovements in Elec;

tric Seam V ldJng Machines,A f which the following is akspqcilication. v

My invention relates to electric sem welding machines in which the seam to be welded is brought to thc-.Jequisite welding temperature by means of its resistance to tlle\{i'ass:1ge ot an electric "current of high amperage and lou voltage through or across it. The current is applied by means of a 4suitable metallic roller or rollers which by preference also supplies the necessary ressure tovcomplete the welding of the ]oint, the roller or rollers progressively engaging the vseam to be welded throughout its length.

'l`he object of the. invention is to provide n simple, positively acting apparatus for quickly and etl'eetirely joining pieces or parts olf metal together h v :i scum weld.

'lo this end the invention consists in the improved construction of electric welding machine hereinafter more particularly described and then speeilied in the claims.

l'n the accompanying drawings, Fig. l is :l side elm-'ation of an electric seam welding machine constructed iu accordance with this invention.

Fig. is a front elevation of the same.

Fig. Il is zi. plan View ol' that portion of the machine showing the feed screw device for. the roller electrode and the automatic current control.

F ig. 4 is an enlarged detached sectional view of the spring pressure device used to apply the necessary welding pressure to the electrode.

Fig. 5 is an enlarged vertical cross-see- .tion through the gear train and attendant.

mechallism liv which the ,feed screw for causing the work-engaging electrode to travel hoth forward und reverse is actuated.

Fig. (i is a vertical cross-section through the feed screw nut or slide and illustrates the device for absorbing the shock when the -the work, said electrodes movable relatively one to the other, and at least one of said electrodes, for instance that indicated at 2, being a. roller adapted to traverse the lapping or otherwise resented marginal portions Aof the materia in order .to produce a continuous seam or weld,

'curved sheets of metal of any style, length or width. The seam maybe formed along 4the lapped or abuttededges of the same piece or sheet of metal or dilerent sheets and also may be formed in overlapped metal intermediate the' edges. The s eets may be lapped any desired amount but wdhen al weld 251g] be mlade alor lthe e ges. tley re era are a e s1 itlv less than theliwidth'oyf the trgalds or lvor emitacting;r surfaces of the electrodes between which the work is' gri ped.

The work to be welded is suitably held by clamps' or otherwise on a. horn or mandrel 1 forming one of the electrodes of the machine. Clam s as well as other means for properly holiling the work in adjusted position on the mandrel l are well known in the art and of various kinds nccordin to the natur-cof the work and as such hol ing means forms no part of my present invention'. illustration and description of such parts herein` is dispensed with, it being undeistood that any suitable means for' this f purpose may be employed.

The mandrel or lower electrode 1 is preferably a flat elongated bar preferably supported in a stationary posit-ion in the machine. whereas the. upper electrpde 2 i's a roller or disk mounted in a carriage for movement in a rectilinear path and into contact with the stationary electrode or 105 mandrel 1, but it is to be understood that th'e invention is not limited to a stationary electrode and a mov'able roller electrode as other. kinds and relations of electrodes may be employed without departing from the "o spirit of the invention. The mandrel or statxonary electrode 1 comprises a single )ieee or bar of copper or other goed con ucting,r material, sutantially rectangularl in cross-section andY'llas-its top edges bevelled to produce a narrow tread'surface. The bar 1 is as long as and preferably lon er than the length of the. 4seam to be wel( ed, the tread surface being approximately equal in lWidth to thewidth of the scam, depending on the amount of overlap. The bar 1 is seated and supported in an a'rm 3 secured to and projecting forwardly from 'the front of the main .frame 4 of the machine.

The roller electrode. 2 -is composed of .a mass 4of copper or other good electrical eon ducting material, theedge portions of which are beveled so as to produce a tread surface, the width of which isequal substantially to the width of the tread surface of stationary electrode l, (sce Fig. 2). Said roller electrode is carried 'by an arbor 5 which is mounted in any suitable way in hearings of a Yswinging arm't, said arm being forked or slotted as shown in Fig. 2 to permit the roller electrode' to rotate freely within the slotted portion..fThe carrying arm 6 is supported for pivotal movement on avspindle mountedA in depending lugs 8 of a carriage 9.', Said carriage is fitted snugly to the under side of an overhan'ging rigid arm 10 forming onemember of the frame 4 and rejecting forwardly' from said frame mem er so as to occupy a horizontal position over stationary electrode l.` The arm 10 is provided at its lower edge with lateral flanges ll constituting a. track or guidcway for the carriage 9, the respective side portions of which are provided with opstanding flanges l2 which embrace the laterallyT extending flanges '11, as shown in Fig. 2, whereby the carriage is fitted slidalily to thc under side oflhe arm l0. Said carriage is provided with upstanding liolts i3 on which are loosely fitted wear plates i4 which are pressed forcibly into contact. with the upper surfaces of the track flanges ll h v springs lll which loosely encircle the bolts lil. and 1lu tension of which springs is adapted to llo regulated hy adjusting.r the nuts 1:'1 on said bolts. The wear plate-r; :ll and spring;r IG provide means for retaining the carriage 9 into close frictional contact with thc umh-r surface of the arm l0, thus compensatingY for xvi-ar duc to the frictional engagement of the moving.r part 9 with the stationary part l0` hut at thc same liant-,said carriage 9 is frmto more in rectilinear path along the guidcway alloidcd h v thil orerhanging arm l0 so as to impart a traversing movement lo the. roller elm-.trollo 2.

The requin-d mechanical pressure from he roller electrode 2 lo the material under treatment is secured by piimgcrs 1T, one of plungers 17 are positionedat the respective 'sides of carriage 9 (see 4Figl'l2), and are fitted slidabl in uidcs 18 provided on said carriage.4 T e p lingers are pressed downwardly by the action, ofspr'ing's 19 incased within the guides 18, and said plungers are in contact at theirlower end portions with arms 20, which .are rigid with the pivotcd arm (i. The plungers 1T' act to depress the arm 6 and thus press the roller electrode 2 into electrical and mechanical vcontact with the lapped portions of the metal to be welded and as a. traversing movement is imparted to the roller electrode 2 current is supplied by thc zo-operatingelectrodes 1, 2 to said lapped portions of the metal for the urpose of render-in cient y plastic to respon to the pressure which is applied by 4themovement of the or mandrel 1, as a result of which the plastic metal is rolled practically to the gage of the metal constituting the work.

For imparting the traversing movement.

to the carriare 9 and roller electrode 2, I employ a feedscrew 21, atraveller 22 and a nut 23, substantially as 'shown in Figs. 1 and 3. V Said traveller 22 is fitted for sliding movement in a. horizontal path on lguideway 24 forming a. part of the vmachine yframe 4;

.the same suli 4 roller-electrode over the stationary electrode and in order to cpn'nect thetraveller 22 with the carriage 9 a'bar ,or link 25j is used` the? same bein housed or contained within a ehambered part ofthe machiaeoframe 4 as indicated in dotted lines 'in Flil and the respective end portions of said link or bar 25 are connected pivotally with traveller 22 and carriage 9. The traveller is provided with upstanding arms 26 between which is located the nut 23. Said nut is connect/ed with traveller 22 for a limited sliding movement hetgeen the upstanding arms 26 in order to permit absorbing!` the shock on reversing the movement of the traveller 22 at the end of its stroke as will be hereafter described and furthermore the nut as a whole is in threaded engagement with the threads on the feed screw 21 whereby rotative movement of the feed screw imparts movement to the nonrotative nut 23 which iu turn is communicated to the traveller 22 through the arms 26. The feed screw 21 is unitary with a drive shaft 30 journallcd in suitable hearings provided on the frame 4 and upon a gear housing 3l, the latter beingthe drive shaft 30 and the said loose gear 36' ia'v in mesh with an' idler 441, which in turn 'beyond the gear honsing, X

meshes with the gear 39 fast on the motordriven -shaft 35. The other loose gear 37 meshes directly with the gear 40 on the 'motor-driven shaft and thus the gears 36, 37 are normali driven in opposite dircc- .tions to each ot er by th shaft 35, but said fgears 3G, 37 do not 'communicate motion to the shaft 30 or. the feed screw 2l except when one ofsaid gears 36, 37 is made fast with said shaft 30'. The operation of making the gear 36 or the ear 37 fast-with the ahaft'30 is accomplis mounted on, a shaft 43 in the gear housing 3 1, said clutch 42 being positioned between the gears 36, 37'and adapted to engage with clutch faces provided on said gears or to be retained in a neutral position intermediate clutchis controllable in a way by the traversing movement of the traveller 22, but means areprovided also, for manually throwin :the clutch into operative engagement wit the ear 36 for the purpose of starting'the mac ine into operation.

The clutch shaft 43 protrudes at one end to which protruding end is mounted a ed lever 46 andaI loose lever 44, the upper part of the loose lever 44 being expanded to form a camshaped head 45, the cam surfaces of which are oppositely inclined to each other, as shown in.Fig. 1. The upper pan; of this lever 46 is provided with lugs 47. 48 straddling the respective sides of the loose lever 44 and adapted to engage therewith. The lower end of the lever 46 is formed with a toe-piece 49 engaged by a latch 5() piroted on the machine frame 4, and to this latch is connected a link 51, the lower end of which is pivoted to a bellcrank 52, the depending arm of said bellcrank being pivotcd to a rod 53 which is pressed in one direction .by aspring 54, said rod being iiivotcd to a foot-trcadle 55 positioned within convenient reach of the operator stationed at thc front of themachine. With the latch 50 in engagement-with the lcvcr 46, the clutch is locked in a neutral position -free from engagement. withthe gears 36. 37, but when it is desired to sci. tln.-..machine into operation the attenrlaht"\ires.ses thc treadle 55 and withdraws latch 50 from lever 46. which releases a spring 56. thereby pressing :i roller 57 forcibly against one cam snrfal-'e of lever 44. This rotates lthe shaft 43 and moves the clutch into engagement with the gear 37. as a result of which the fccd sr-rcw is rotated in one direction so as to act on the nnt 23 and impart traveling movement, to the trav# eller 22, whereby the thrust har 25 is actuated to impart movement to the carriage 9 and traversing movemcntvis thereby irnparted to the roller elect rode with respect to the stationary electrode. The clutch is autoed by a clutch 42" .with the lever 44. said gears. The, means for operating the ported .in a bracket 61 attached to the gearusing 31, said rockshaft being with a. de of which lspivoted a bar 63, the other end of which has a pin and slot connection 64 Said horizontal har 58 carries two stops 65, 66, which are adjustably fastened to said har 58, and with these stop's co-operates a pin 67 attached to one of the arms 2 6'0f traveller 22, said pin 6T being positioned for movement'between the stops 65. 66. As the traveller 22 moves forprovided wardly under the action of -tlle screw, the

pin 67 approaches the stop 65, and when the traveller and the pin reachthe limit of their forward movement, said pin strikes the stop 65 and imparts movement to the bar 58, the latter operating torock the shaft 60 and swing the link 62 in a direction toimpart movement 'to the har 63, the operation of which imparts rocking movement to the lever 44 so as to swing it against lug 47 of lever 46. At this time roller .57 is on the opposite incline of the cam of lever 44 andthe spring 56 (notY being held by latch 50) thcnacts to swing levers 44 and 46 as a unit to Totale tbc shaft 43. and thus shift. the clutch 42 from the gear 37 over to and into engagement with the gear 3G, the result of whichis to reverse the direction of rotation of the feedscrew 21. The Vscrew now acts on thenut 23 to more the traveller 22 in a reverse direction, thus drawingr thc carriage 9 and the roller electrode 2 backward- I y over the welded scum. such reverse movement taking place until thepin 67 strikes the other stop 66, wherenpon-the bar 58 and roclrshaft 60 are operated to impart movemcnt in a. reversa direction to thc bar 63, and thus return the levers 44 :1nd,46 to initial position wherein tha clutch 42 is free from engagement. with gears 36 or 3T. This stops the operation of the machine. ,thc lever 46 being again held in position engaged by the latch 50 which acts to lock the clutch in a. neutral position. the spring 56 being prevented from acting by the latch 50.

The spring 56 heretofore described is :mchorcd at one end to the'goar housing. its other and being attached to a lever 6R, said lever bein'g pivoted on the gear housing and being provided intermediatc its ends with a lug on which ismounted the roller 57, as

pending link 62, to the lower end ilfi Y parts and to sudden reversal of travel of *To overcome th e inertia of the moving absorb the shock due to the the nnt23 when the direction of rotation of the feed screw is reversed at the time the roller electrode reaches the end'of its tra-vel in either direction, and thereby prevent loosening ofcr damage to the various parts of the machine, I referably arrange said 'nut so that it wi lact as a shock absorbing' device as will non? be described. The feed.' nut 23 is held from rotative movement with respect to the traveller 22 by a'bar 95 secured Vto the un- 'dcrside of the ltraveller and passin rloosely through acorrcspondingly former groove i :the nut, asshown in' Fig. 6. The nut is rovided. wiithlan elongated sleeve 23' which lies threaded engagementwith feed screw 21.' For convenience in assembly, the sleeve 23 is made as a separate part.. The sleeve' 23'f. is however rigidly secured to the' part 23,' so -that to all intents and purposes the twol parts fonna'unitary whole. The. sleeve 23' is adapted to slide in bcaringsfcrmed in 'the traveller 22 to a limited'extent inde-A pendent ofany r'novexncnt of the traveller,

. between the part 23 of the nut having a lost motion the arms 2G of the traveller to perimit this .independent motion.

96 indicates spindles passing loosely through the nut 23 and bearing atv opposite "ends against the arms- 26. Coil springs 97 disposed on the' spindles 96 within the body the nut 23 bear at opposite ends against a freely slidable washer 98 and a freely slidable sleeve 99.

When the roller electrode Q 'and its car- "riage 9 and consequently the traveller 22.

:reach the end .of the stroke in one direc- 'tion, the rotation of theifeedscrew 21 is suddenly reversed as previously described. .Instead of a sudden blow to-the traveller and its attendant parts as would be the case were the connection between the nut and the traveller a rigid one. any shock due to the reversing of the feed screw is absorbed by the springrs 9? as it is only through these springs that the shift in movement can be transmitted to thc traveller 22.- 'Tfhe lost motion between the nut23 and the traveller 22 permits those springs to act in en ob- "lOllS nllnllcl. V

The' machine disclosed herein embodies n. transformer positioned within a'chaxnbered part of the main frame 4 whereby' the weight of said transformer is not iuposed on the movable part of the machine.l such as thel clement which carries the movable clcctlodc. indicates the primary of the transformer and 71 the seccndary'fwhich yieldable to the cam, surfaces of 4 4 when said lever is operated due l to the action ofl 1 eautomatic stops 65v desired cr arrangement coniiecte'd'aQjliQQ tothe lower horn or arm 3 and th'efother is electrically ccnnected at 101 :tb' tl1e overhanging arm 10,

alof'thesecondary is electrically current Ibein iconducted to the roller elecl trodethroug the carriage 9 and pivcted arm `6, a shunt-connection' 72 ably providedto prevent arcing as wellfas being prefer?" to provide a good connection ar'oundp-:lthenl pivot of the arm 6.

In this as: 1n other types of a 'arat'us in this class the flowo'f current The' cw. of current across the electrodes 1s dependent upcnthe contact of. roller electrode 2 with the lapped metal, and upon the operation of a cut-out or circuit controller 'i34 supported on a bracket 102 and connected ,in theprimary circuit of the transformer as shown in-Fg. 1.

rtionsof the This cut-out comprises. stationary contact 75 and a movable contact 76, the latter crunlr, having a trig er arm 82'. The trigger arms 75.' and 82 ora-operate with stops,

or fin rs `8'6, 87 respectively,carried 'on a shifta le bar- 88. One ,end oftlieshiitable bar 88 1s .supported in an upstandipg'arm 89 of the carrier 9, said arm extend1ngnpwardly through u. slotin-Ithe'overhangng .rigidi arm 10, but the other end ofthe honzontal bar 88 1s pivot'ed to the forward arm 26 of-traveller22.. normal position diary devices desircdto be employed and ordinarily used i this oonnbctlcn in this los webpagina vin-a.-

art so las to' prevent the llowcf current to' the electrodes 1.2 in the normal the mechanism. As the elec ef2 makes contact with the lapped marginal rtions of the metal, the tinger-86 is carri 'byrthe ition 0f f leo forward movement of the traveller. andf'by engaging the trigger-'ann 75', swings thevibratory arm 77 andmoves the contact 76 into electrical engagement wthcontact 75,

and thus establishes the .How of current to electrodesl and 2,. the effect of which s'to4 render plastic the metal under; treatment, and as the electrode 2 traverses the metal .and the electrodelythc metal is pressed together and weldutoQpi-gtuce a contiguous las seam. At this time the contacts 7.5 and 76 are heldl together by the detent 79, being 1ocated'beneath tlie"de1:ent 81. By the time that the electrode 2 completes its forward movement, the stop'87 strikes the trigger 'arm 82', and actuates the arm 82 thus free-4 ingr the detent 79 from the detent 81, allow! ing the spring 78 to rockathe arm 77 and break the'circuit. The switch members bel ing held-apart during the return .stroke of the machine by the spring 7 8. During the rever-se, or return movement of the traveller 22, and bar 88, the ti r 86 must pass under the trigger arm To permit this,

l the finger 8`6 is pivotally mounted in such way that it slipsunder the tri ger 75 on the return movement, but on te forward movement,'it strikes the trigger rigidly.

The operation of the machine is as follows: The work is placed on the lower mandrel4 .or stationary electrode 1 'in' proper position.l The operator presses on the trcadle 55 and the motor is thereby actuated to im part fthe traversing movement to roller elec- Atrode 2, currentj being supplied to said electrode 2 and the electrode 1 to render the metal plastic. The roller electrode travels between the work holders and over electrode 1 to effect the welding progressively. for the 3 reason that the meta is rendered plastic as the roller passes along said metal, and said roller cooperates with electrode 1 in applying the pressure required to eifectthe union of the marginal portions of the metal, as a result of which a continuous seam is prn duced'which affords a satisfactory union between the marginal portions, the application of pressure rolling the metal along the seam down to the gage of the individual 4 sheets are welded in the manner described. As the roller electrode reaches the limit of its movement, the cut-out operates to preclude the fiow of current, and the driving4 46 mechanism then becomes eli'ective in imparting reversemotion to the carriage and to the roller electrode so as to return said parts to their initial positions.

vObviously the various current carrying parts f the machine may be and preferably are supplied 'with water circulating means to keep the .various parts cool as is the customary practice in the art.

It will be understood that-the invention is not limited to the details of construction and arrangement of parts as shown and describedexcept as may be specified in the ap ended claims. Y

at I claim as my invention is: 1. In an electric seam welding machine,

pieces composing the sheets. in case two the combination with a. roller electrode and a co-operating electrode, one of said :electrodes '.beiiig bodily movable with relation to tlie other, of a feed screw for the movable electrode, reversible driving means for said'feed screwand 4a. shock absorbing dethe combination of a. roller electrodeI-a rela.

tively stationary electrode, a` carriage on whchthe roller electrode is mounted, a feed screw, a nut connected with'said carri and threaded 4on the feed screw, reversib e driving means for said feed screw-and a f shock absorbing device interposed in the connection between said nut and said electrode and actin" upon the reversal of rota-- tion of said fee screw.

4. In an electric seam welding machine, the combination of a roller electrode, a rela- 90 tively 'stationa ry electrode co-operating with said roller electrode, `a carriage on which the roller electrode is' mounted, a feed screw` a traveller connected to said carriage a feed mit associated with said traveller and threaded on said feed screw, reversible driving means for said feed screw and n. shock absorbing device interposed between said nut and said traveller. Y

5. In an electric seam, welding machine, the combination of a roller electrode,a relatively stationary electrode co-ope'ating'with said roller electrode, n carriage on whichithe roller electrode is mounted, a feedscrew, a traveller connected to said carriage, a. feed mit connected with said traveller and threaded on said .feed screw, reversible driving means for said feed screw and springs' interposed ,between said nut and said traveller andadapted to act as a shockdl absorber on reversing 'the rota'tion' of said feed screw. s j i Si ed at L nn in the county of Essex' and i tate of assachusetts this 26th day of November A. D. 1918.

GUs'rAvE H. s'cHKoMMoDAU. i Wisse.

Gnome E. lgziimw. 

